1. Field
The present disclosure relates to an organic light-emitting display device in which the thickness of pixels is uniform, and a method of manufacturing the organic light-emitting display device.
2. Description of the Related Technology
An organic light-emitting display device may be classified as either a passive matrix (PM) organic light-emitting display device or an active matrix (AM) organic light-emitting display device according to the driving method thereof. In passive matrix organic light-emitting display devices, anodes are generally arranged in columns, and cathodes are arranged in rows. A row driving circuit applies scanning signals to a group of anodes in units of rows. In addition, a column driving circuit applies a data signal to each pixel. In active matrix organic light-emitting display devices, the input of a signal to each pixel is controlled by a thin film transistor (TFT). Thus, active matrix organic light-emitting display devices are appropriate for processing a large amount of signals, and thus have been used to display moving pictures.
In an active matrix organic light-emitting display device, a passivation layer is typically disposed on TFTs as a protecting layer and a layer for planarizing an upper surface of the TFTs. In addition, pixel defining layers (PDLs) are typically disposed on the passivation layer.
Pixel defining layers are generally formed to a thickness that is large enough to prevent mixing of colors between adjacent pixels, so that the thickness of the pixel emission areas between the pixel defining layers may vary. When the pixel defining layer is formed as an organic layer, outgassing may occur as a result of chemical decomposition over a short or long time duration. The outgas may flow into the pixel emission areas, thereby degrading the organic light-emitting display device, resulting in, for example, pixel shrinkage or reduced lifetime.